Bob Sirott of WMAQ-Ch. 5. (NBC photo)

Bob Sirott of WMAQ-Ch. 5. (NBC photo)

(WGN-AM)- Bob Sirott, long expected to take over Warner Saunder's 10 p.m. anchor chair on WMAQ-Ch. 5, instead is leaving the NBC-owned station three weeks after Saunders' retirement.

Sirott, a veteran Chicago radio and television personality and former CBS News correspondent, already had replaced Saunders as co-anchor on Channel 5's 5 p.m. and 6 p.m. newscasts and has been Allison Rosati's primary co-anchor at 10 p.m. in place of Saunders for several months.

A clause already in Sirott's current multi-year contract assured him of the 10 p.m. broadcast, but sources say the station sought to shorten the guaranteed terms in exchange for actually naming him to the position and negotiations failed to produce a settlement.

WMAQ will likely use other anchors such as Marion Brooks, Dick Johnson and Rob Stafford in Sirott's place, with Stafford, a former "Dateline NBC" correspondent, seen as having the inside track.

"We appreciate all that Bob has done for us for the last three-and-a-half years," WMAQ executive Frank Whittaker said in a memo to staff this morning, noting Sirott will continue to work with Chicago Tribune parent Tribune Co.'s WGN-AM 720.

(The Chicago Tribune contributed to this story)

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